On-site paint mixing has long been available at retail outlets such as paint stores and hardware stores. This offers great convenience and savings of time, both for lay consumers and for professional contractors.
Caulk sealant is used to join, for example, wood or synthetic trim to painted surfaces; laminates at their seams or to walls; sinks to counters, flooring to painted, laminated or wood surfaces; and so on. Traditionally, caulk could only be purchased in the color white. Recently, a limited range of fixed colors became available on the retail level. One company will provide, from its factory, caulks with colors which are custom matched to a particular manufacturer's laminates.
To date, no company is known to have produced an apparatus which allows the contractor or the home hobbyist to go to his local paint store, present a color sample to be matched, and purchase tubes of caulk specifically blended on the store's premises to duplicate the color of his paint, tile, laminate, or the like. The problem has been that, unlike paint, caulk is very viscous. Therefore, there are problems in mixing the tinting agent with the caulk and in dispensing the caulk into the tubes which are used in caulk guns, since it cannot readily be poured.
The advantage of having color matched caulk is that a great saving of time is possible. The user does not have to apply the paint itself with precision at joining edges or, alternatively, does not have to paint over white caulk previously applied. The user may first paint next to, but not exactly on, the joint and then afterwards fill in the unpainted surface with caulk.
Prior developments in this field may be generally illustrated by reference to the following patents:
______________________________________ Patent No. Patentee Issue Date ______________________________________ 3,951,387 F. Warden et al. 04/20/76 2,965,363 L. D. Worden 12/20/60 2,927,410 L. Doyen et al. 03/08/60 4,190,371 H. Durr et al. 02/26/80 3,516,220 C. G. Buford et al. 06/23/70 1,446,047 G. J. Keller et al. 02/20/23 4,758,096 K. Gunnarsson 07/19/88 2,831,606 M. E. Alters 04/22/58 ______________________________________
Most of these patents teach mixing systems and filling systems in which pistons are used to displace the product and are representative of what is in that art.
The patent to Alters, U.S. Pat. No. 2,831,606, shows a single container being used both for stirring and dispensing. However, it does not collapse--rather, it uses a plunger which is combined with the stirrer. Worden, in U.S. Pat. No. 2,965,363, shows a system that dispenses color and then mixes it in containers.